Kind: captions
Language: en
the evergiven one of the largest
container ships ever built
plows into the bank of the suez canal
it completely blocks one of the most
important shipping lanes in the world
for nearly a week triggering a global
emergency
the costco galaxy which was almost
exactly the same size forged a smooth
passage through the waterway despite
having to battle the same windy
conditions
why did one ship sail through the canal
safely
and the other crash
francesco overlays the tracking data of
the ever given and the costco galaxy
the resulting image lays bare the
different paths of the two ships
as they entered the canal the wind
pushed both ships towards the left bank
the ever given veered particularly close
both ships then slightly increased their
speed as they approached a bend
this would have made them more
maneuverable the more water that rushes
past a ship's rudder the faster it turns
but halfway through the bend the galaxy
slowed back down
while the ever given sped up
the difference
the difference between the two is that
they went through the curve of the canal
at different speeds
the costco galaxy kept the moderate and
constant speed
they ever given increased its speed up
to nearly 14 knots
in strong winds big ships are often
easier to control the faster they go
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but within the confines of the canal
high speeds can cause problems
when a shift like the ever given nears
the side of the canal hydrodynamic
effects suck the ship towards the
nearest bank
this is called bank effect
and the bigger the speed
the bigger the bank effect
as the ever given moved through the
canal
its vast bulk displaced hundreds of
thousands of tons of water
this rushed past the hull and formed a
bow wave at the front
francesco believes that as the ship got
close to the bank
the bow wave formed a cushion
that pushed the bow away
but further back
as the gap between ship and bank
narrowed the water flowed faster when a
fluid speeds up pressure in the fluid
drops which in this case created suction
that pulled the stern towards the bank
just a small increase in speed leads to
a big increase in this so-called bank
effect
francesco's analysis suggests that the
ever given's high speed caused it to
lurch from experiencing bank effect on
one side of the canal to bank effect on
the other
and eventually to crash